Measuring fluoride in human saliva and water

  • Kwestan Muhammad Department of Clinical Biochemistry, College of Health Sciences, Hawler Medical University, Erbil, Iraq.
  • Salim K. Mohammed Department of Clinical Biochemistry, College of Health Sciences, Hawler Medical University, Erbil, Iraq.
  • Kamaran Y. Mohammadamin Department of Clinical Biochemistry, College of Medicine, Hawler Medical University, Erbil, Iraq.
  • Victor Kuri Lecturer at School of Biological and Marine Sciences, Faculty of Science and Engineering, Plymouth University, Plymouth, UK.
Keywords: Fluoride, Dental caries, Saliva


Background and objective: Fluoride is used to prevent dental caries, and it has been one of the most effective and widespread agents. Fluoride level has been shown in saliva, plaque, and oral soft tissues after use of fluoridated toothpaste that persists at potentially active concentrations for hours. This study aimed to evaluate how fluoride in toothpaste intake can affect the salivary fluoride and test fluoride in tap water in the different places of Erbil city.

Methods: Forty five volunteers were examined. In the morning after overnight fasting before brushing teeth, the saliva of the subjects (healthy non-smoker adults) was taken before brushing teeth, which was a baseline. After 10 and 20 minutes of washing mouth with water (after brushing), saliva was taken and then the cotton pad was held under the tongue for 5 min. Saliva samples were frozen at -20 Co for later analysis. Tap water samples in different places in Erbil city were analyzed.

Results: Toothpaste significantly (P = 0.002) increased salivary fluoride after brushing teeth. The fluoride concentration of tap water in Erbil city was very low at the places that use groundwater.

Conclusion: This research indicates that salivary fluoride significantly increases after brushing teeth. The fluoride concentration naturally occurring levels in the tap water in the places where the source is groundwater are not enough.


Sloof, W, Eerens H, Janus J, Ros J. Integrated criteria document: Fluorides; 1989. (Report No. 758474010). Bilthoven: National Institute of Public Health and Environmental Protection. (Accessed March 1, 2017, at

Amerongen VAN, Bolscher AJ, Veerman E. Salivary proteins: Protective and diagnostic value in cardiology? Caries Research 2004; 38:247–53.

Lawrence HP. Salivary markers of systemic disease: non-invasive diagnosis of disease and monitoring of general health. J Can Dent Assoc 2002; 68(3):170–4.

Carranza M, Ferraris ME, Galizzi M. Structural and morphometrical study in glandular parenchyma from alcoholic sialosis. J Oral Pathol Med 2005; 34(6):374–9.

Hu S, Denny P, Xie Y, Loo JA, Wolinsky LE, Li Y et al. Differentially expressed protein markers in human submandibular and sublingual secretions. Int J Oncol 2004; 25(5):1423–30.

Schipper RG, Silletti E, Vingerhoeds MH. Saliva as research material: Biochemical, physicochemical and practical aspects. Arch Oral Biology 2007; 52(12):1114–35.

Aps JKM, Martens LC. Review: The physiology of saliva and transfer of drugs into saliva. Forensic Science International 2005; 150(2-3):119–31.

Duckworth RM, Morgan SN, Gilbert RJ. Oral fluoride measurements for estimation of the anti-caries efficacy of fluoride treatments. J Dent Res 1992; 71(Spec No):836–40.

Lagerlof F, Oliveby A. Caries-protective factors in saliva. Adv in Dent Res 1994; 8(2):229–38.

Ole Fejerskov and Edwina Kidd. Dental Caries: The Disease and Its Clinical management. 2nd ed. Blackwell Publishing; 2008. P.38.

Oliveby A, Lagerlof F, Ekstrand J, Dawes C. Studies on fluoride concentrations in human submandibular/sublingual saliva and their relation to flow rate and plasma fluoride levels. J Dent Res 1989; 68(2):146–9.

Dawes C, Weatherell J. Kinetics of fluoride in the oral fluids. J Dent Res (Spec Issue) 1990; 69:638–44.

Lagerlof F, Oliveby A, Ekstrand J. Physiological factors influencing salivary clearance of sugar and fluoride. J Dent Res 1987; 66(2):430–5.

Naumova EA, Kuehnl P, Hertenstein P, Markovic L, Jordan RA, Gaengler P, et al. Fluoride bioavailability in saliva and plaque. BMC Oral Health 2012; 12:3.

Alarcon-Herrera MT, Martin-Dominquez I, Trejo-Vazquez R, Rodriquez-Dozal S. Well water fluoride, dental fluorosis, bone fractures in the Guadiana Valley of Mexico. Fluoride 2001; 34(2):139–49.

Kurttio P, Gustavsson N, Vartiainen T, Pekkanen J. Exposure to natural fluoride in well water and hip fracture: A cohort analysis in Finland. Am J Epidemiol 1999; 150(8):817–24.

Burt BA. The changing patterns of systemic fluoride intake. J Dent Res 1992; 71(5):1228–37.

How to Cite
Muhammad, K., Mohammed, S., Mohammadamin, K., & Kuri, V. (2019). Measuring fluoride in human saliva and water. Zanco Journal of Medical Sciences (Zanco J Med Sci), 23(2), 242-246.
Original Articles